A Single-centre Study of Entonox Versus Midazolam Sedation in Gastroscopy

A Single-centre, Randomised Controlled Study of Entonox Versus Midazolam Sedation in Gastroscopy.

This study aims to determine whether Entonox (gas and air) is at least as good as intravenous midazolam in providing analgesia and sedation during gastroscopy. Entonox is used as an adjunct in lower gastrointestinal procedures but is not routinely used in gastroscopy, and there is only one similar published study to date, which was performed in children. The main advantage of Entonox over midazolam is the quick recovery time following withdrawal of the agent, which enables patients to return to independent normal life. The investigators would like to be able to offer Entonox to patients as an option for sedation during gastroscopy, this study is being conducted to determine if it is a safe and feasible option.

Inclusion Criteria:

• Male/female aged 18 years or over
• Confirmed clinical requirement to undergo diagnostic gastroscopy
• Suitable for sedation
• Able to provide informed consent

Exclusion Criteria:

• History of chronic respiratory or significant cardiac disease
• Requirement for longer procedure eg Barrett's surveillance
• Previous known adverse reaction to Entonox
• Entonox use in previous 4 days
• Known current vitamin B12 or folate deficiency
• Unable to provide consent
• Any known contraindication to Entonox:
• Gas trapped in a part of the body where its expansion may be dangerous, such as air lodged in an artery or artificial traumatic or spontaneous pneumothorax (collapsed lung).
• Decompression sickness (the bends) or following a recent dive
• Air encephalography
• Severe bullous emphysema
• Myringoplasty
• Gross abdominal distension
• Recent severe injuries to the face and jaw
• Current or recent head injuries
• If the patient has recently had any eye surgery where injections of gas have been used